ABSTRACT
Objective:To analyze a family clustering of coronavirus disease 2019 （COVID-19） associated with the exposure to an asymptomatic case， and to provide evidences of developing strategies for COVID-19 prevention. Methods:Epidemiological investigation was conducted on a COVID-19 family cluster （1 confirmed case and 2 asymptomatic cases）. The specimens of the cases were tested for 2019 novel coronavirus nucleic acid with real-time fluorescence quantitative polymerase chain reaction. Results:The clustering epidemic occurred in a family. Two asymptomatic cases B and C （B’s son） had Wuhan residential history. After arrival in Beijing on January 24， 2020， B stayed in his mother's house. One family member A （B’s mother） developed the disease on February 7， 2020， while the other two family members D and E （B’s wife and brother） did not develop the disease， and they were managed as close contacts. Conclusion:Thisfamily COVID-19 clustering is induced by the exposure to an asymptomatic case. Identification of asymptomatic cases is very important for the control of COVID-19 epidemic.
ABSTRACT
Objective:To conduct epidemiological investigation of a family cluster of coronavirus disease 2019 （COVID-19） in Fangshan District， Beijing， so as to provide reference and scientific basis for the strategy of prevention and control. Methods:Based on the "Prevention and Control Plan for COVID-19 （Third Edition）"issued by the National Health Commission of China， two cases from the same family were studied by field epidemiological investigation method. Sputum and/or throat swab specimens were collected and sent to the laboratory of Fangshan District Center for Disease Control and Prevention （CDC） for nucleic acid detection of 2019 novel coronavirus （2019-nCoV）. Tracking close contacts and isolation observation were conducted. Results:Both sputum and throat swab specimens of case 1 were positive for 2019-nCoV nucleic acid on February 3rd， 2020. Case 2 （wife of case 1） received screening as a close contact， and throat swab specimen was positive on February 4th， 2020. Therefore， it was determined to be a family cluster. The epidemic was effectively controlled after a series of measures， including isolation treatment， medical observation according to management of close contact and terminal disinfection of residence. Conclusion:The CDC professionals should strengthen monitoring of new findings， comprehensively analyze case data based on the latest research trends， improve professional sensitivity， and conduct timely screening to detect cases as soon as possible for the prevention of further epidemic spreading.